1. Field of the Invention
This invention relates to a tilting-pad bearing or a bearing having a plurality of tilting-pads.
2. Description of the Prior Art
A tilting-pad bearing is arranged such that a plurality of bearing pads are tiltably supported at center portions of their outer peripheries by pivot means and disposed about a periphery of a rotary shaft so as to define bearing spaces between the bearing pads and the outer periphery of the rotary shaft, fluid being sucked by the action of rotation of the rotary shaft into the bearing spaces to urge an inlet ends of the bearing pads thereby causing the bearing spaces to be shaped into a wedge-like configuration in section, and the fluid being flowed by the wedge action into the wedge-like bearing spaces to form a fluid film having a high pressure so that the rotary shaft is floated and supported by the fluid film. Such a tilting-pad bearing is described in, for example, a Japanese journal of "THE HITACHI ZOSEN TECHNICAL REVIEW," 1977, Vol. 38, No. 4.
In general, the tilting-pad bearing of the kind specified above is provided with seal members on side portions of the bearing pads to facilitate the entry of the lubricating fluid into the spaces between the shaft and the bearing pads. However, when the shaft rotates at a high speed, not only the mechanical loss is increased by the lubricating fluid existing in narrow gaps between the seal members and the shaft, but also heat generated in these portions is transferred through the lubricating fluid to the bearing pads to raise the temperature of the bearing fluid film, thereby resulting in the risks that seizure is caused and that the reliability is lowered. Moreover, in such a tilting-pad bearing, there must be provided the seal members, and spherical couplings or pin connections are utilized as pivot means for determining the tilting position of the bearing pads and thus the parts are increased in number and the construction is complicate.